Talk:Quantum entanglement

How to frighten the horses: imply that Q E could be used to xmit information instantaneously. Susan Jayne Garlick^talk 21:41, 3 September 2007 (CDT)

Oh, perfect. AS could link to that as another "violation" of relativity. Surprised he hasn't jumped on that yet. Actually I'd better mention that in the article right now. Wouldn't want frightened horses, would we?--Bayes^infer 22:03, 3 September 2007 (CDT)

Would it be possible to use something similar to digital signal processing to use quantum entanglement to send information? Rather than encoding it on the particles themselves, you could just 'spin' the particles at a predetermined rate. For example, every 10ns you can move a particle from '1' (as determined by direction) or move/keep it at '0' and then have someone at the other end read it. Then you send a special bitcode signal to say that you're done sending information. I heard it from a guy who knows a guy, want to know if that's sound.

No. ADK^{...I'll widen your xanthochroi!} 14:05, 14 September 2011 (UTC)

Does doing that destroy the entanglement or is it because you can't observe the same state or what? ^{— Unsigned, by: 75.199.219.39 / talk / contribs}

Any time where you can know the spin of a particle, the entanglement is destroyed. The only time entanglement exists is when two particles are in a superposition - they're really the same thing, a superposition exists because you don't know the states of the entangled particles. In order to send information via spin-coupling, you need to know what the spin is at your end much in the same way you need to know, at your end, if you've just made a dot or a dash when sending morse code, otherwise you're sending information free noise - and to do that means pulling it out of a superposition, which means the entanglement is destroyed. Removing the entanglement just gives you a probabilistic collapse from a superposition to a known state, meaning you get random noise at both ends which no information can be encoded in. It's effectively identical at both ends, but there's no information transmitted because it's randomised. There is absolutely no way to get around this. Any time you want to manipulate a particle, you remove the entanglement and such manipulation is what is needed for meaningful information to be encoded. Indeed, if you assume the hidden variables interpretation the appearance of entanglement and action-at-a-distance is just an illusion anyway. ADK^{...I'll yank your Pope!} 09:34, 15 September 2011 (UTC)

In fiction

The Korean series 'I am not a Robot' features a device using quantum entanglement among other things (including two amusing 'bad minions'). Anna Livia (talk) 18:20, 5 September 2019 (UTC)